1. Field of the Invention
The present invention pertains to exhaust mufflers for water craft, and more particularly to wet marine exhaust mufflers shaped to conform to the hulls of small motorized water craft.
2. Description of the Related Art
Motorized water craft typically include exhaust mufflers for muffling or attenuating exhaust noise generated by operation of the marine engine. Such mufflers must be capable of handling not only the exhaust gases themselves but also droplets of water injected into the exhaust gas stream from the cooling system of the engine. The water injected from the engine cooling system typically performs two functions, namely, absorbing engine exhaust noise and cooling the exhaust gases so that they might be safely discharged through the hull of the craft without presenting a fire hazard.
Mufflers of various designs have been placed in the exhaust conduit running between the engine and the discharge. Examples of marine exhaust systems include Miles et al., U.S. Pat. No. 5,259,797; Miles et al., U.S. Pat No. 5,147,232; Tazaki et al., U.S. Pat. No. 5,096,446; Winburg, U.S. Pat. No. 4,781,021; Harbert, U.S. Pat. No. 4,019,456 and U.S. Pat. No. 4,000,786 (Ford). Often, marine muffler designs are closely akin to the mufflers used on automobiles but are constructed of materials such as fiberglass which can better tolerate the marine environment.
The engine compartments of small boats tend to be cramped, and bulky marine mufflers do not readily fit within such small spaces. Additionally, many of the marine mufflers, such as that described in U.S. Pat. No. 4,000,786 (Ford) are roughly cylindrical in shape and do not fit easily in the tapering hull of a small boat. Accordingly, there remains a need in the art for a wet marine exhaust muffler with minimal space requirements. There is an even more specific need for such a muffler that functions via reactive and absorptive principles to effectively attenuate sound.